ONOMASTIC Meaning of ONOMASTIC in English onomastic BrE AmE ˌɒn ə ʊ ˈmæst ɪk ◂ AmE \ ˌɑːn oʊ- -ə- ▷ onomastic|s s Longman Pronunciation English Dictionary. Английский словарь произношений Longman. 2012